This invention relates to an expansion seal for cable pipe.
An expansion seal can be applied to different diameter cable pipe by the expansion force of an elastic sealing ring hereinafter referred to as elastic ring to seal the pipe to prevent liquid or moisture entering into the cable pipe. The expansion seal can have a simplified structure and can be installed or separated quickly by fastening or loosening bolts without changing any element.
In general, the same nominal external diameter electric cable pipes or transmission pipes may have a different inner diameter because of different manufacturing tolerance, the difference ratio always being below 10%. The end of the cable pipe should be sealed to prevent liquid, mud or moisture entering the cable pipe, otherwise, the cable may be damaged and an operator's life put in peril. Thus it is necessary to provide seals of various sizes to apply for different diameters of cable pipe. This raises manufacturing costs and causes operative inconvenience or disturbance.